While some people wear glasses constantly, others wear them only intermittently or change from clear to tinted glasses depending on the ambient light conditions. It is desirable to have a clip attached to a temple bar of the glasses to engage the edge of a shirt pocket thereby preventing the folded glasses from falling out when bending over. Many attempts at the ideal design and method of this clip have been made over the years. Some involve modification of the temple bar or permanent attachment of the clip to the temple bar at the time of manufacture. Other attachable clips are cumbersome to mount, alter the appearance of the glasses substantially, involve expensive manufacture, provide non rigid attachment, or are conformable to a limited range of temple piece cross sections.
Among the prior art patents include U.S. Pat. No. 1,779,015 of Schmitt, which teaches temple clips that are either molded as one piece with the temple bar or attached by riveting or by a clamp form fit to the temple bar cross section. U.S. Pat. No. 1,898,059 of McDonald discloses a temple clip attached with a split barrel clamp and retained with a set screw. With respect to removable retrofit clips for eyeglass temple bars, U.S. Pat. No. 4,903,375 of DiFranco describes an inexpensive plastic clip which simply attaches to a variety of temple pieces through the use of two rubber "o" rings. This retrofit system of DiFranco '375 is not a rigid attachment however. Furthermore, U.S. Pat. No. 5,235,727 of McCloskey teaches several embodiments of an attachable pocket clip made of an elastically deformable material, such as a U-shaped spring steel clasp. Like DiFranco '375, McCloskey '727 does not teach a rigid attachment, and its U-shaped embodiment does not provide a secure fit. Different designs are used for different temple piece cross sections.
Moreover, U.S. Pat. Nos. 4,316,654 and 4,496,224, both of Allen, teach eyeglass frames with pocket clips where the frames themselves are manufactured with pocket clips attached to the rims of eyeglass lenses. U.S. Pat. No. 5,414,906 of Kren discloses an eyeglass storage clip attached to a temple piece with a dual barrel design. It consists of several parts and uses spring clips to attach to a garment or pocket.
The disadvantages of the prior art are either that the temple bar pocket clips are difficult to assemble or assemble when the eye glasses are manufactured, as in Schmitt '075, McDonald '059, Allen '654, Allen '224 or Kren '906, or that the retrofit configurations of DiFranco '375 or McCloskey '727 are flimsy and not designed for long term rigid attachments.